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تسجيل مستخدم جديدConstraint on the growth factor of the cosmic structure from the damping of the baryon acoustic oscillation signature
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Gen Nakamura
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We determine a constraint on the growth factor by measuring the damping of the baryon acoustic oscillations in the matter power spectrum using the Sloan Digital Sky Survey luminous red galaxy sample. The damping of the BAO is detected at the one sigma level. We obtain sigma_8D_1(z=0.3) = 0.42^{+0.34}_{-0.28} at the 1sigma statistical level, where sigma_8 is the root mean square overdensity in a sphere of radius 8h^{-1}Mpc and D_1(z) is the growth factor at redshift z. The above result assumes that other parameters are fixed and the cosmology is taken to be a spatially flat cold dark matter universe with the cosmological constant.
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